在Windows上运行? Windows default命令是一个PowerShell终端。

  - name: SET CURRENT_BRANCH
    run: |
      $branchName = "${{github.ref}}".Split("/")["${{github.ref}}".Split("/").Length -1]
      echo "::set-env name=CURRENT_BRANCH::$(echo $branchName)"

要将其设置为环境变量，我使用以下语法:

- name: Extract branch name
  shell: bash
  run: echo "::set-env name=BRANCH_NAME::$(echo ${GITHUB_REF#refs/heads/} | sed 's/\//_/g')"
- name: Test
  run: echo "${BRANCH_NAME}"

我发现这个语法在这里:Github动作-启动worflows#如何定义环境变量?# 68

Rmq: sed 's/\//_/g'将用_替换分支名称中的/

你可以使用https://github.com/rlespinasse/github-slug-action

# Just add this  => 
- name: Inject slug/short variables
  uses: rlespinasse/github-slug-action@v3.x



# And you get this  => 
- name: Print slug/short variables
  run: |
    echo "Slug variables"
    echo " - ${{ env.GITHUB_REF_SLUG }}"    
    echo " - ${{ env.GITHUB_HEAD_REF_SLUG }}"
    echo " - ${{ env.GITHUB_BASE_REF_SLUG }}"
    echo " - ${{ env.GITHUB_REPOSITORY_SLUG }}"
    # output e.g. : master feat-new-feature v1.0.0 product-1.0.0-rc.2 new-awesome-product
    echo "Slug URL variables"
    echo " - ${{ env.GITHUB_REF_SLUG_URL }}"
    echo " - ${{ env.GITHUB_HEAD_REF_SLUG_URL }}"
    echo " - ${{ env.GITHUB_BASE_REF_SLUG_URL }}"
    echo " - ${{ env.GITHUB_REPOSITORY_SLUG_URL }}"
    # output e.g. : master feat-new-feature v1-0-0 product-1-0-0-rc-2 new-awesome-product
    echo "Short SHA variables"
    echo " - ${{ env.GITHUB_SHA_SHORT }}"
    # output e.g. : ffac537e

下面是一个适用于push和pull_request事件的完整工作流

name: whichBranch
on: [pull_request, push]

jobs:
  which_branch:
    runs-on: ubuntu-latest
    steps:
      - name: Extract branch name on push
        if: github.event_name != 'pull_request'
        shell: bash
        run: echo "::set-env name=BRANCH_NAME::$(echo ${GITHUB_REF#refs/heads/})"
        id: extract_branch

      - name: Extract branch name on pull request
        if: github.event_name == 'pull_request'
        run: echo "::set-env name=BRANCH_NAME::$(echo ${GITHUB_HEAD_REF})"

      - name: Print branch name
        run: echo 'The branch name is' $BRANCH_NAME

同时处理pull_request和push事件的解决方案。由于set-env已弃用，因此实现了保存获得的分支名称以供后续步骤使用的变通方法。 不需要第三方操作。

name: CI
on: [ pull_request, push ]
jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - name: "Get branch name and save to env"
        env:
          IS_PR: ${{ github.EVENT_NAME == 'pull_request' }}
        run: |
          if ${IS_PR}; then
            BRANCH_NAME="${GITHUB_HEAD_REF}"
          else
            BRANCH_NAME="${GITHUB_REF##*/}"
          fi
          echo "BRANCH_NAME=${BRANCH_NAME}" >> $GITHUB_ENV

      - name: "Another step uses branch name"
        run: echo "Branch name is ${{ env.BRANCH_NAME }}"

GitHub动作中的运行时变量

注意，如果你在pull request触发器上执行你的GitHub动作，那么GITHUB_REF变量将包含类似refs/pull/421/merge这样的东西，所以如果你尝试git push到那个名字，它很可能会失败。

你可以在YAML中使用GitHub上下文中的引用。比如:${{github。head_ref}}

https://help.github.com/en/actions/automating-your-workflow-with-github-actions/contexts-and-expression-syntax-for-github-actions#github-context